/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */
package org.apache.causeway.commons.internal.base;

import lombok.experimental.UtilityClass;

/**
 * package private utility for {@link _Strings}
 */
@UtilityClass
class _Strings_HtmlEscaper {

    // as declared int guava's com.google.common.html.HtmlEscapers
    // order matters: replace '&' first
    private final _Strings.KeyValuePair[] replacements = {
            _Strings.pair("&", "&amp;"),
            _Strings.pair("<", "&lt;"),
            _Strings.pair(">", "&gt;"),
            _Strings.pair("\"", "&quot;"),
            // Note: "&apos;" is not defined in HTML 4.01.
            _Strings.pair("'", "&#39;"),
    };

    String htmlEscape(final String input) {
        if(_Strings.isEmpty(input)) {
            return input;
        }

        String output = input;

        for(_Strings.KeyValuePair replacement : replacements) {
            output = output.replace(replacement.getKey(), replacement.getValue());
        }

        return output;
    }

}
